LONDON —
At a bail hearing in London Friday, a lawyer for the militant Jordanian cleric Abu Qatada said his client would be willing to return to Jordan to face terrorism charges, if the country’s parliament ratifies a recently-negotiated treaty with Britain that bans the use of evidence obtained through torture.

Some commentators are calling this a “game changer” in the British government’s more than decade-long legal battle with Abu Qatada.

Britain has been trying to deport him back to Jordan since shortly after he was convicted of terrorism there in 1999 in a trial he did not attend. But various courts have blocked the effort, including the European Court of Human Rights, saying evidence allegedly gathered through torture might be used against him. There are claims that men whose statements were used against Abu Qatada were tortured.

Abu Qatada would face a retrial if he returned to Jordan. Last month, Britain’s Home Secretary Theresa May told Parliament she had negotiated a new treaty with Jordan that would ensure any evidence obtained through torture will not be used in the retrial.

“I can tell the house that I have signed a comprehensive mutual legal assistance agreement with Jordan," said May. "This agreement is fully reciprocal, offers considerable advantages to both countries, and reflects our joint commitment to tackling international crime."

If Jordan’s parliament ratifies the treaty, a process that could take months, Abu Qatada would again face deportation. But he could still try to fight it in the British and European courts. Friday’s offer would appear to promise he won’t do that, in an effort to convince the court to let him out of jail in the meantime.

At London’s King’s College, Research Fellow Frank Foley said Friday’s offer could be significant, but warns it may not signal an early end to the case.

“The Jordanians have given substantial legal undertakings - a stringent ban on the use of torture-obtained evidence. One would have assumed that he will want to fight his case all the way, like he has done for 10 years now," he said. "I wouldn’t rule out potentially further embarrassing developments for the British government in the future if Abu Qatada changes his mind.”

Foley also said the British government is not likely to accept any deal to grant bail, and the court will probably not take the lawyer’s offer into account out of concern that Abu Qatada might try to flee. The next hearing is set for May 20.

In Britain, Abu Qatada is accused of violating immigration rules. A Spanish judge said he was al-Qaida’s top operative in Europe, and he allegedly has links to other terrorist groups, including one in Germany and one in Chechnya.

He also issued an Islamic ruling endorsing the killing of converts from Islam in Algeria, along with their wives and children. And he has advocated killing Jews and praised attacks on Americans.

Fifty-two-year-old Abu Qatada, whose real name is Omar Mahmoud Mohammed Othman, applied for political asylum in Britain in 1993. In recent years, has been in and out of British prisons.

(In an earlier version of this story Frank Foley was incorrectly identified as James Foley.)